Refrigerator cars with floor conveyers are presently used by the railroads to carry relatively rugged perishable lading, for example, potatoes in bulk. Many of the cars have both longitudinal conveyers which feed to the center of the car, and a transverse conveyer which feed out the side door. See, for example, AAR Designation RSB & RPB type cars. Many of these cars presently have side racks which slope to the center and sections of racks which cover the longitudinal conveyer.
When the cars are loaded the racks are all in place. A telescopic loading conveyer loads the car from the ends toward the center. The large side door is closed and the center section is loaded through a small door in the top center of the main door.
Unloading is accomplished by connecting a power source to a drive shaft extension which operates the longitudinal and transverse conveyers in the car. Track side conveyers are connected to the small unloading door in the main side door. The product in the center section is unloaded first, and when empty, the main side door is then opened. An operator then removes the first section of floor rack exposing a part of the longitudinal conveyer. Product not sliding off the side sloped rack is manually moved to the conveyer. The operator progresses down to the end of the car, removing succeeding sections of the floor rack. When the car has been emptied the side and floor racks can be leveled and the car can be used as a refrigerated or nonrefrigerated box car.
U.S. Pat. No. 3,738,511 discloses a railway car which is convertible from an insulated box car to a box car having hoppers for the transport of bulk cargo.